Abstract
Purpose
The aim of this study was to determine the impact of polymorphic variant rs1739843 of the hspb7 gene on clinical profile and outcomes in patients with hypertrophic cardiomyopathy (HCM).
Methods
The study population consisted of 108 patients with HCM ≥45 years old. The control group included 192 healthy donors. A novel disease pathway model, firstly designed in foreign outcome study (2017), was employed to assess clinical course of HCM. SNP rs1739843 of the hspb7 gene was genotyped by allele-specific real-time polymerase chain reaction (PCR) assay.
Results
It was found a significant increase in TT genotype frequency of rs1739843 of the hspb7 gene in patients with HCM (n=108) – 20.4%, compared with control group (n=192) – 4.2% (TT: TC+CC, odds ratio (OR) = 5.88, 95% confidence interval (CI) = 2.52–13.75, p<0.001). High prevalence of CC genotype of rs1739843 of the hspb7 gene was observed in control group – 80.2% vs 31.5% in HCM (CC: TC+TT, OR = 0.11, 95% CI = 0.07–0.19, p<0.001). The allele frequency (C: T) also differed between HCM and control groups – 55.6: 44.4% in HCM, vs 88.02: 11.98% in control group (OR = 5.88, 95% CI = 3.91–8.85, p<0.001). It was also found a significant increase in TT genotype frequency of rs1739843 of the hspb7 gene in HCM patients with benign course free of adverse pathways (n=48) – 16.7%, compared with control group (n=192) – 4.2% (TT: TC+CC, OR= 4.60, 95% CI = 1.63–12.99, p<0.001)). The allele frequency (C: T) in HCM patients with benign course free of adverse pathways was 56.3: 43.7% vs 88.02: 11.98% in control group (OR = 5.71, 95% CI= 3.44–9.49, p<0.001). The mortality rate of HCM patients with 1, 2 or 3 adverse pathways was higher compared with HCM patients with benign course free of adverse pathways. HCM patients ≥45 years old showed a significant increase in T allele frequency in cases of presence of 2 (CHF (chronic heart failure) III–IV functional class (NYHA) + AF (atrial fibrillation)) and 3 adverse pathways (CHF III-IV functional class (NYHA) + AF + SCD (sudden cardiac death) of HCM progression.
Conclusions
The T allele and TT genotype of rs1739843 of the hspb7 gene were more frequent in patients with HCM ≥45 years old, compared with control group. It was also found a significant increase in frequency of TT genotype and T allele of rs1739843 of the hspb7 gene in HCM patients with benign course free of adverse pathways, compared with control group. HCM progression along 2 and more adverse pathways in patients ≥45 years old has been characterized with adverse outcome. Allele T of rs1739843 of the hspb7 gene was associated with 2 and more adverse pathways of HCM progression.
Prevalence and Clinical Profile of Myocardial Crypts in Hypertrophic Cardiomyopathy
