HIF1A and Myocardial fibrosis: However, Wei et al.'s study[81]indicate that HIF-1 gene knockout exacerbates pressure overload-induced myocardial fibrosis, cardiomyocyte hypertrophy, reduced myocardial capillary density, and cardiomyocyte apoptosis, promoting the occurrence of heart failure, suggesting a protective role of HIF-1 in the hearts of pressure-overloaded mice.