Plasma circulating donor-derived cell-free DNA (ddcfDNA) can be used to noninvasively monitor acute rejection of heart transplants (HTx). This study utilized digital droplet PCR to analyze ddcfDNA concentrations (measured in copies per milliliter) and the fractional abundance (%ddcfDNA) to differentiate between donor and recipient DNA on the basis of single nucleotide polymorphism (SNP) homozygosity. Seventy-seven patients participated in a study, providing 300 plasma samples. Both markers, mean ddcfDNA (cp/mL) and %ddcfDNA, showed similar decreasing trends following the HTx, (R2 < 0.2; p < 0.001). Significantly higher levels of ddcfDNA (cp/mL) and %ddcfDNA were observed during episodes of acute rejection (AR) compared to non-rejection samples (p < 0.001). Additionally, antibody-mediated rejection (AMR) was associated with increased %ddcfDNA levels compared to non-rejection and to acute cellular rejection samples (p < 0.001 and p < 0.01). A logistic regression model identified %ddcfDNA as an early predictor of AMR risk 10-19 days post-heart transplant (odds ratio 158, p < 0.02). Performance analysis established an optimal %ddcfDNA threshold of 0.125% for AMR detection, correctly identifying all patients without subsequent AMR. These findings suggest that early %ddcfDNA measurements post-HTx can accurately identify individuals unlikely to develop AMR during the first posttransplant year.

• Klíčová slova
• SNP, biomarker, cfDNA, rejection, transplantation,
• MeSH
• biologické markery * krev   MeSH
• časná diagnóza MeSH
• dárci tkání * MeSH
• dospělí MeSH
• isoprotilátky * imunologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• následné studie MeSH
• přežívání štěpu MeSH
• prognóza MeSH
• rejekce štěpu * diagnóza   etiologie   krev   MeSH
• rizikové faktory MeSH
• transplantace srdce * škodlivé účinky   MeSH
• volné cirkulující nukleové kyseliny * krev   genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• biologické markery * MeSH
• isoprotilátky * MeSH
• volné cirkulující nukleové kyseliny * MeSH

BACKGROUND: Cardiac allograft vasculopathy (CAV) is an accelerated form of coronary artery disease (CAD) that is characterized by concentric fibrous intimal hyperplasia along the length of coronary vessels, and is recognized as long-term complication after heart transplantation. The chromosomal loci 9p21, 6q25.1, and 2q36.3, represented by their respective leading variants rs10757274, rs6922269 and rs2943634, have been linked with a history of CAD by genome-wide association studies. We aimed to investigate the associations of genetic variants at the loci 9p21, 6q25.1, and 2q36.3 with CAV as genetic risk factors for early prediction. METHODS: Genomic DNA was extracted from paired aortic samples of 727 heart recipients (average age 50.8 ± 12.2 years; 21.3% women) and corresponding donors (average age 39.7 ± 12.0 years; 26.1% women). The variants within the loci 9p21, 6q25.1, and 2q36.3 were genotyped using PCR-RFLP. RESULTS: The recipients' variants of 9p21 (OR 1.97; 95% CI, 1.21-3.19 for GG vs. +A comparison, p = 0.0056) and 2q36.3 (OR 2.46; 95% CI, 1.12-6.17 for +C vs. AA comparison, p = 0.0186) were associated with higher incidence of CAV during the first year following heart transplantation. No such association was found for donor genotypes. CONCLUSIONS: Our data suggest that variants at the locus 9p21 (rs10757274) and 2q36.3 (rs2943634) are associated with early CAV development.

• Klíčová slova
• SNPs, cardiac allograft vasculopathy, transplantation,
• MeSH
• alografty patologie   MeSH
• celogenomová asociační studie MeSH
• dospělí MeSH
• genetická predispozice k nemoci MeSH
• jednonukleotidový polymorfismus * MeSH
• lidé středního věku MeSH
• lidé MeSH
• lidské chromozomy, pár 2 * genetika   MeSH
• lidské chromozomy, pár 6 genetika   MeSH
• lidské chromozomy, pár 9 * genetika   MeSH
• nemoci koronárních tepen * genetika   etiologie   patologie   MeSH
• transplantace srdce * škodlivé účinky   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

The current standard for graft rejection surveillance is endomyocardial biopsy (EMB), an invasive procedure with rare but potentially serious complications. Detection of circulating donor-derived cell-free DNA (ddcfDNA) is an option for noninvasive monitoring of graft injury and rejection. A 63-year-old man and a 65-year-old woman were monitored by EMB for allograft rejection. A total of 48 single-nucleotide polymorphisms with a minor allele frequency range of 0.4-0.5 were screened to distinguish donor and recipient DNA based on homozygosity, and digital droplet PCR was used to analyze ddcfDNA concentrations. Both subjects suffered rejection within the first 6 months after transplantation. The maximal ddcfDNA level of 270 copies (cp)/ml during EMB-confirmed acute cellular rejection (ACR; mild grade 1R/2, patient 1), and the maximal concentration of 1,846 cp/ml in the case of EMB-confirmed antibody-mediated rejection (AMR; grade 1+; patient 2), was detected. Individual monitoring of ddcfDNA dynamics from the 1st to the 6th month posttransplant reflected cardiac graft injury in patients suffering ACR or AMR, meaning that ddcfDNA may serve as a noninvasive biomarker.

• Klíčová slova
• biomarker, cfDNA, rejection, transplantation,
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

Reaching critically short telomeres induces cellular senescence and ultimately cell death. Cellular senescence contributes to the loss of tissue function. We aimed to determine the association between variants within genes involved in telomere length maintenance, posttransplant events, and aortic telomere length in heart transplant patients. DNA was isolated from paired aortic samples of 383 heart recipients (age 50.7 ± 11.9 years) and corresponding donors (age 38.7 ± 12.0 years). Variants within the TERC (rs12696304), TERF2IP (rs3784929 and rs8053257), and OBCF1 (rs4387287) genes were genotyped, and telomere length was measured using qPCR. We identified similar frequencies of genotypes in heart donors and recipients. Antibody-mediated rejection (AMR) was more common (p < 0.05) in carriers of at least one G allele within the TERF2IP locus (rs3784929). Chronic graft dysfunction (CGD) was associated with the TERC (rs12696304) GG donor genotype (p = 0.05). The genetic risk score did not determine posttransplant complication risk prediction. No associations between the analyzed polymorphisms and telomere length were detected in either donor or recipient DNA. In conclusion, possible associations between donor TERF2IP (rs3784929) and AMR and between TERC (rs12696304) and CGD were found. SNPs within the examined genes were not associated with telomere length in transplanted patients.

• Klíčová slova
• SNP, genetic risk score, heart transplantation, rejection, telomere,
• MeSH
• DNA metabolismus   MeSH
• dospělí MeSH
• genetické lokusy MeSH
• leukocyty metabolismus   MeSH
• lidé středního věku MeSH
• lidé MeSH
• telomery * genetika   MeSH
• transplantace srdce * škodlivé účinky   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA MeSH

BACKGROUND: Implantation of left-ventricular assist systems (LVASs) has become the standard of care for advanced heart failure (HF). The absence of pulsatility in previous devices contributes to vascular and endothelial dysfunction related to atherosclerotic or vascular complications. We hypothesized that the artificial pulsatility provided by the HeartMate 3 (HM3) (Abbott, Chicago, IL) LVAS would exert a favourable effect on the vasculature. METHODS: In 32 patients implanted with HM3 (5 female patients, mean age 55 ± 13.6 years), the reactive hyperemia index (RHI) and peripheral augmentation index (AI), markers of endothelial function and arterial stiffness, were measured with an EndoPAT2000 before and in the third and sixth month after implantation. RHI and AI data from 30 HeartMate II (HM II) (Abbott) recipients in the third and sixth month after implantation, from 15 patients with advanced HF without LVASs and from 13 healthy volunteers were also analyzed. RESULTS: In HM3 recipients, the mean RHI significantly decreased at 3 and 6 months after implantation. The RHI was substantially lower at baseline than that of healthy or the HF reference group. Increasing AI values, indicating worsening arterial stiffness, were also observed. Similar trends were observed in HM II recipients between the third and sixth months but with higher absolute values of RHI and AI. CONCLUSIONS: We detected impaired vascular function in HM3 patients and provided additional evidence on the negative effect of low pulsatility on vascular function after LVAS implantation. The results suggest that the artificial pulsatility of the HM3 does not avert the progression of endothelial dysfunction.

• MeSH
• arterie patofyziologie   MeSH
• časové faktory MeSH
• cévní endotel patofyziologie   MeSH
• cévní rezistence fyziologie   MeSH
• funkce levé komory srdeční fyziologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• následné studie MeSH
• podpůrné srdeční systémy * MeSH
• prospektivní studie MeSH
• srdeční komory patofyziologie   MeSH
• srdeční selhání patofyziologie   terapie   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• pozorovací studie MeSH
• práce podpořená grantem MeSH

BACKGROUND: Implantation of current generation left ventricular assist devices (LVADs) in the treatment of end-stage heart failure (HF), not only improves HF symptoms and end-organ perfusion, but also leads to cellular and molecular responses, presumably in response to the continuous flow generated by these devices. MicroRNAs (miRNAs) are important post-transcriptional regulators of gene expression in multiple biological processes, including the pathogenesis of HF. In our study, we examined the influence of long-term LVAD support on changes in flow-sensitive miRNAs in plasma. MATERIALS AND METHODS: Blood samples from patients with end-stage heart failure (N = 33; age = 55.7 ± 11.6 years) were collected before LVAD implantation and 3, 6, 9, and 12 months after implantation. Plasma levels of the flow-sensitive miRNAs; miR-10a, miR-10b, miR-146a, miR-146b, miR-663a, miR-663b, miR-21, miR-155, and miR-126 were measured using quantitative PCR. RESULTS: Increasing quantities of miR-126 (P < 0.03) and miR-146a (P < 0.02) was observed at each follow-up visit after LVAD implantation. A positive association between miR-155 and Belcaro score (P < 0.04) and an inverse correlation between miR-126 and endothelial function, measured as the reactive hyperemia index (P < 0.05), was observed. CONCLUSIONS: Our observations suggest that after LVAD implantation, low pulsatile flow up-regulates plasma levels of circulating flow-sensitive miRNAs, contributing to endothelial dysfunction and vascular remodeling.

• Klíčová slova
• Endothelial dysfunction, Left ventricular assist device, Plasma, miRNA,
• MeSH
• dospělí MeSH
• kvantitativní polymerázová řetězová reakce MeSH
• lidé středního věku MeSH
• lidé MeSH
• mikro RNA * genetika   MeSH
• podpůrné srdeční systémy * MeSH
• pulzatilní průtok MeSH
• senioři MeSH
• srdeční selhání * diagnóza   genetika   terapie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• mikro RNA * MeSH