To validate the role of SMAD3 in USP7 knocking out-mediated beneficial effects in this HFpEF model, we constructed AAV9-ENT vectors (based on adeno-associated virus 9 (AAV9) serotype modification and enhanced the infection efficiency of vascular endothelial cells) carrying SMAD3 under the ICAM2 promoter. The gene discussed is NT5E; the disease is infection.