library_construction_protocol: Mice were anesthetized with 0.2 mL/10 g Avertin of body weight and the heart was perfused with sterile ice-cold PBS using a miniplus peristaltic pump (~1ml/heart/min, GILSON) for 10 min to clear red blood cells. Cardiac single cells were obtained using the Multi Tissue Dissociation Kit 2 (Cat# 130-110-203, Miltenyi Biotec) according to manufactures protocols. This kit removes most of the cardiomyocytes during the procedure and the cutoff of single cell viability from each sample was ~90%. Libraries preparation and sequencing were performed at the Sequencing Facility, Frederick National Laboratory for Cancer Research. Briefly, ~16.5K cells were collected for each sample, and Chromium Next GEM Single Cell 3ʹ Reagent Kits v3.1 and Chromium Next GEM Single Cell 5' reagent v2 dual index kits were used for the AngII/PE mouse model and the MI model, respectively.