Hypertrophic Cardiomyopathy in Underrepresented Populations: Clinical and Genetic Landscape Based on a Russian Single-Center Cohort Study.

Hypertrophic cardiomyopathy (HCM) is a common inherited cardiac disorder characterized by marked clinical and genetic heterogeneity. Ethnic groups underrepresented in studies may have distinctive characteristics. We sought to evaluate the clinical and genetic landscape of Russian HCM patients. A total of 193 patients (52% male; 95% Eastern Slavic origin; median age 56 years) were clinically evaluated, including genetic testing, and prospectively followed to document outcomes. As a result, 48% had obstructive HCM, 25% had HCM in family, 21% were asymptomatic, and 68% had comorbidities. During 2.8 years of follow-up, the all-cause mortality rate was 2.86%/year. A total of 5.7% received an implantable cardioverter-defibrillator (ICD), and 21% had septal reduction therapy. A sequencing analysis of 176 probands identified 64 causative variants in 66 patients (38%); recurrent variants were MYBPC3 p.Q1233* (8), MYBPC3 p.R346H (2), MYH7 p.A729P (2), TPM1 p.Q210R (3), and FLNC p.H1834Y (2); 10 were multiple variant carriers (5.7%); 5 had non-sarcomeric HCM, ALPK3, TRIM63, and FLNC. Thin filament variant carriers had a worse prognosis for heart failure (HR = 7.9, p = 0.007). In conclusion, in the Russian HCM population, the low use of ICD and relatively high mortality should be noted by clinicians; some distinct recurrent variants are suspected to have a founder effect; and family studies on some rare variants enriched worldwide knowledge in HCM.

Overlapping Phenotype of Adult-Onset ALPK3-Cardiomyopathy in the Setting of Two Novel Variants.

Inherited cardiomyopathies (CMPs) are fairly common causes of morbidity and mortality, particularly, in young individuals. In substantial number of cases, only morphological diagnostic criteria cannot distinguish one CMP from another because of incomplete penetrance, advanced stage of the disease, or overlapping phenotypes. Genetic testing has become a mandatory tool for definite diagnosis that is required for family screening, individual prognosis, and personalized treatment strategy in routine practice. In parallel, accumulation of genotype-phenotype correlations, especially for rare genes, promotes the deciphering of underling molecular mechanisms and the development of targeting treatment of CMPs. Here we present an adult-onset case comprised morphological features of several CMPs: asymmetric left ventricle (LV) hypertrophy, severe systolic dysfunction, LV hypertrabeculation and restrictive physiology. Using next-generation sequencing, two novel variants (NM_020778.5:c.1958C>G:p.Ser653* and c.3491G>A:p.Arg1164Gln) in alpha-protein kinase 3 (ALPK3) gene were identified and confirmed with Sanger sequencing. The trans-position (location on different alleles) of identified ALPK3 variants was established by plasmid cloning method. The ALPK3 gene, encoding nuclear alpha-protein kinase 3, has only recently been associated with CMPs and there are still few clinical data on ALPK3 variant carriers. To date, only five affected individuals with adult-onset CMPs in the setting of biallelic variants of ALPK3 gene have been reported.

Risk Stratification after an Acute Coronary Syndrome: Significance of Antithrombotic Therapy.

The impact of the de-escalation strategy of antiplatelet therapy (APT) on the life expectancy after acute coronary syndromes (ACS) and percutaneous coronary intervention (PCI) requires an assessment in real clinical practice. Into the Russian multicentral observational trial (ORACLE II ClinicalTrials.gov number, NCT04068909), 1803 patients with ACS and PCI indications were enrolled. During 12 months of follow-up, 228 all-cause deaths have occurred. The analysis of death predictors was carried out by the classification tree method. Age, an option of antithrombotic therapy, a history of chronic heart failure, and uric acid level had the greatest prognostic value. The death prediction model's sensitivity was 82.1% in the training cohort and 79.2% in the test cohort. During the observation period, ticagrelor was replaced with clopidogrel (APT de-escalation) in 357 patients. The groups of patients with different antiplatelet therapy options were adjusted for clinical parameters by the pseudorandomization method. The de-escalation group had the lowerest all-cause death rate. The incidence of bleeding and recurrent nonfatal coronary events in the study groups did not differ significantly. Thus, the APT regimen's advantage of changing from the maximum in the first weeks after ACS to moderate at follow-up has been confirmed. There is an obvious need to study the possibilities of individualizing antiplatelet therapy in patients after acute coronary syndromes.

Switching of Oral Anticoagulation Therapy After PCI in Patients With Atrial Fibrillation: The RE-DUAL PCI Trial Subanalysis.

OBJECTIVES: The aim of this study was to assess if prior oral anticoagulant agent (OAC) use modifies the lower bleeding risk observed with dabigatran dual therapy (dabigatran twice daily plus a P2Y12 inhibitor) versus warfarin triple therapy (warfarin plus a P2Y12 inhibitor plus aspirin) in patients with atrial fibrillation who underwent percutaneous coronary intervention (PCI). BACKGROUND: In the RE-DUAL PCI (Randomized Evaluation of Dual Antithrombotic Therapy With Dabigatran Versus Triple Therapy With Warfarin in Patients With Nonvalvular Atrial Fibrillation Undergoing Percutaneous Coronary Intervention) trial, the primary outcome of major bleeding or clinically relevant nonmajor bleeding was lower with dabigatran dual therapy versus warfarin triple therapy in patients with atrial fibrillation who underwent PCI. METHODS: A total of 2,725 patients were randomized to dual therapy with dabigatran (110 or 150 mg twice daily) plus clopidogrel or ticagrelor or triple therapy with warfarin plus aspirin and clopidogrel or ticagrelor. Subgroup analysis compared risk for major bleeding or clinically relevant nonmajor bleeding and a composite thromboembolic endpoint in patients with prior OAC use and in those who were OAC treatment naive. RESULTS: Risk for major bleeding or clinically relevant nonmajor bleeding was reduced with both dabigatran dual therapies compared with warfarin triple therapy in both the prior OAC use group (hazard ratios: 0.58 [95% confidence interval (CI): 0.42 to 0.81] and 0.61 [95% CI: 0.41 to 0.92] with 110 and 150 mg dabigatran, respectively) and the OAC-naive group (hazard ratios: 0.49 [95% CI: 0.38 to 0.63] and 0.76 [95% CI: 0.59 to 0.97] with 110 and 150 mg dabigatran) (p for interaction = 0.42 and 0.37, 110 and 150 mg dabigatran, respectively). The risk for thromboembolic events seemed similar with dabigatran dual therapy (both doses) and warfarin triple therapy across subgroups. CONCLUSIONS: Bleeding risk was reduced with dabigatran dual therapy versus warfarin triple therapy in patients with atrial fibrillation after PCI, regardless of whether they were prior OAC users or OAC treatment naive. These results suggest that it is also safe to switch patients on OAC pre-PCI to dabigatran dual therapy post-PCI.

Association of the CYBA, PPARGC1A, PPARG3, and PPARD gene variants with coronary artery disease and metabolic risk factors of coronary atherosclerosis in a Russian population.

Abnormalities in lipid metabolism and enhanced oxidative stress are considered as major risk factors for coronary atherosclerosis. Functional genetic variations in genes whose products are involved in lipid metabolism and antioxidant defense could therefore modulate risk of coronary artery disease (CAD). In this study, we evaluate whether the PPARGC1A Gly482Ser, PPARG3 (-681)C/G, PPARD +294T/C, and CYBA +242C/T gene variants confer the risk of CAD in a Russian population. A total of 313 CAD patients and 132 controls with no clinical sign of CAD were studied. The polymorphic markers were tested using a TaqMan assay. Allele and genotype frequencies in CAD patients and controls were compared using the Yates chi(2) test. Association of the genetic markers with metabolic risk factors of arterial atherosclerosis was studied using the analysis of variance test and then adjusted for conventional risk factors in the multiple regression analysis. For CYBA +242C/T, both the allele T and genotype T/T showed significant association with higher risk of CAD (odds ratio =1.49 and 3.89, respectively). The allele C and genotype C/C of the +294T/C marker of PPARD were associated with increased risk of CAD providing an odds ratio of 2.12 and 2.78, respectively. The risk variants of CYBA +242C/T and PPARD +294T/C markers were associated with higher low-density lipoprotein cholesterol and increased total serum cholesterol, respectively. In conclusion, the CYBA +242C/T and PPARD +294T/C variants modulate risk of CAD through their associations with atherogenic serum lipid profiles.

Advanced age, low left atrial appendage velocity, and factor V promoter sequence variation as predictors of left atrial thrombosis in patients with nonvalvular atrial fibrillation.

Atrial fibrillation (AF) renders individual patients at risk for development of an atrial thrombus. The aim of this study was to determine clinical and echocardiographic factors influencing the risk of left atrial thrombosis (LAT) in patients with persistent nonvalvular AF. Genetic variants encoding haemostatic factors have been also assessed for putative association with LAT. In the cross-sectional study, a total of 212 patients (132 males and 80 females) with nonvalvular persistent AF (duration range 48 h-90 days) have been selected. LAT was visualized by transesophageal echocardiography. The FGB G(-455)A, PAI-1 4G/5G, F5 C(-224)T, and F5 R506Q genetic markers were tested using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) approach. To reveal independent factors contributing to the thromboembolic risk in AF, a multivariate logistic model was applied. LA thrombi were found in 44 out of 212 subjects (21%). LAT was more frequently observed in patients at age >75 years (P < 0.001) and those who had reduced left ventricular ejection fraction <40% (LVEF; P < 0.001) and decreased left atrial appendage velocity <20 cm/s (LAAV; P < 0.001). Logistic regression analysis showed that advanced age (OR = 1.64 per decade P < 0.001), LVEF < 40% (OR = 2.12, P < 0.001), LAAV (OR = 1.56, P = 0.007), and TT genotype of F5 C(-224)T (OR = 2.42, P = 0.041) are associated with higher risk of LAT. Age >75 years, LVEF < 40%, LAAV < 20 cm/s, and Factor V C(-224)T variant independently contribute to the thromboembolic risk in AF.

Association of CYP2D6 and ADRB1 genes with hypotensive and antichronotropic action of betaxolol in patients with arterial hypertension.

Betaxolol is a selective antagonist of beta(1)-adrenergic receptors. Personal response to the drug widely varies and depends on its properties and individual features including innate characteristics. Our aim was to study the association between the clinical response to betaxolol in patients with essential hypertension (EH) and polymorphous markers of two genes: beta(1) adrenergic receptor gene (ADRB1) and cytochrome P450 2D6 gene (CYP2D6). Eighty-one patients with EH were selected. Mean age was 52.2 +/- 1.22 years. Betaxolol monotherapy provided effective blood pressure control (BP < 140/90 mmHg) in 68 patients, 56 of them continued treatment with initial dose. The systolic (SBP) and diastolic (DBP) blood pressure declined significantly at the end of the study. We have not found any significant association of rest and exercise BP and heart rate (HR) with polymorphous marker Arg389Gly of ADRB1 gene except the nighttime variability of DBP. But in case of the polymorphous marker Pro34Ser of CYP2D6 gene we have found significant association with response to betaxolol therapy. The rest HR declined more significantly in Ser/Pro genotype carriers (-32.6 +/- 4.77 beats/min and -18.4 +/- 2.01 beats/min, P = 0.023). These patients demonstrated more significant increase of exercise time (4.58 +/- 0.90 and 0.59 +/- 0.58 min, P = 0.045). Maximal exercise HR and DBP were also significantly lower in Ser/Pro genotype carriers in comparison with Ser/Ser genotype carriers. Decline of mean daytime SBP in 24-h ambulatory blood pressure monitoring was more significant in Pro allele carriers (-21.0 +/- 2.55 mmHg vs. -5.2 +/- 2.27 mmHg in patients with Ser/Ser genotype, P = 0.001). Betaxolol effect on HR and BP significantly depends on variability of the gene determining the drug metabolism. The carriers of Pro34 allele of CYP2D6 gene (8.6%) are more sensitive to betaxolol therapy. Because of the relatively small group sizes our data should be considered as preliminary ones. The increase of our groups and the replication in other studies will permit to estimate the contribution of genetic factors to betaxolol effect on HR and BP.