Incidence and prognostic impact of bleeding and transfusion after coronary surgery in low-risk patients.

BACKGROUND: Excessive bleeding and blood transfusion are associated with adverse outcome after cardiac surgery, but their mechanistic effects are difficult to disentangle in patients with increased operative risk. This study aimed to evaluate the incidence and prognostic impact of bleeding and transfusion of blood products in low-risk patients undergoing coronary artery bypass grafting (CABG). STUDY DESIGN AND METHODS: Sixteen tertiary European centers of cardiac surgery contributed to the prospective European registry of CABG (E-CABG). The severity of bleeding was defined by the E-CABG bleeding severity classification and universal definition of perioperative bleeding (UDPB) classification. RESULTS: Of 1213 patients with EuroSCORE II of less than 2% (mean, 1.1 ± 0.4%), 18.5% suffered from mild bleeding (E-CABG bleeding Grade 1) and 3.4% experienced severe bleeding (E-CABG bleeding Grade 2-3). Similarly, 19.7% had UDPB Class 2 and 5.9% had UDPB Classes 3 and 4. Mild and severe bleeding defined by the E-CABG and UDPB classifications were associated with an increased risk of several adverse events as adjusted by multiple covariates. The risk of death, stroke, and acute kidney injury was particularly increased in patients with severe bleeding. CONCLUSION: Severe bleeding is rather uncommon in low-risk patients undergoing CABG, but it is associated with an increased risk of major adverse events. Prevention of excessive perioperative bleeding and patient blood management may improve the outcome of cardiac surgery also in low-risk patients.

Genetic Association Analyses Highlight IL6, ALPL, and NAV1 As 3 New Susceptibility Genes Underlying Calcific Aortic Valve Stenosis.

BACKGROUND: Calcific aortic valve stenosis (CAVS) is a frequent and life-threatening cardiovascular disease for which there is currently no medical treatment available. To date, only 2 genes, LPA and PALMD, have been identified as causal for CAVS. We aimed to identify additional susceptibility genes for CAVS. METHODS: A GWAS (genome-wide association study) meta-analysis of 4 cohorts, totaling 5115 cases and 354 072 controls of European descent, was performed. A TWAS (transcriptome-wide association study) was completed to integrate transcriptomic data from 233 human aortic valves. A series of post-GWAS analyses were performed, including fine-mapping, colocalization, phenome-wide association studies, pathway, and tissue enrichment as well as genetic correlation with cardiovascular traits. RESULTS: In the GWAS meta-analysis, 4 loci achieved genome-wide significance, including 2 new loci: IL6 (interleukin 6) on 7p15.3 and ALPL (alkaline phosphatase) on 1p36.12. A TWAS integrating gene expression from 233 human aortic valves identified NAV1 (neuron navigator 1) on 1q32.1 as a new candidate causal gene. The CAVS risk alleles were associated with higher mRNA expression of NAV1 in valve tissues. Fine-mapping identified rs1800795 as the most likely causal variant in the IL6 locus. The signal identified colocalizes with the expression of the IL6 RNA antisense in various tissues. Phenome-wide association analyses in the UK Biobank showed colocalized associations between the risk allele at the IL6 lead variant and higher eosinophil count, pulse pressure, systolic blood pressure, and carotid artery procedures, implicating modulation of the IL6 pathways. The risk allele at the NAV1 lead variant colocalized with higher pulse pressure and higher prevalence of carotid artery stenosis. Association results at the genome-wide scale indicated genetic correlation between CAVS, coronary artery disease, and cardiovascular risk factors. CONCLUSIONS: Our study implicates 3 new genetic loci in CAVS pathogenesis, which constitute novel targets for the development of therapeutic agents.