The presence of a minor allele at rs2241562 was associated with increased heart failure (HF) incidence in Chinese patients, and differences in myocardial H₂ histamine receptor (HRH2) transcript abundance were seen in participants with dilated cardiomyopathy who responded to beta-blockade. The study evaluated whether HRH2 single nucleotide polymorphisms (SNPs) are associated with HF incidence or myocardial transcript abundance is associated with recovery and included patients from the Multi-Ethnic Study of Atherosclerosis (MESA). Differences in myocardial HRH2 transcripts were characterized in those with dilated cardiomyopathy comparing 6 “super-responders” with 6 non-responders to beta-blockade in the Beta-blocker Effect on Remodeling and Gene Expression (BORG) trial. Researchers found:

• In MESA, no candidate SNP was associated with HF in black, Hispanic, or white participants.
• The rs2241562 minor allele was only present in Chinese participants and the adjusted HF hazard among those with ≥1 copies of this allele was 3.7.
• In BORG, super-responders to beta-blockade had higher levels of myocardial HRH2 transcript at baseline vs non-responders.