SRX14130513 GSM5885676_r1 SRP359249 PRJNA805223 SRS11957077 GSM5885676 GSM5885676 RNA-Seq TRANSCRIPTOMIC cDNA Epicardioids were dissociated with papain as described in methods of Meier et al. (2021), filtered through 40 μm filter, washed with 5 mL 1% BSA (Gibco; 15260037) in PBS-/-, centrifuged for 3 min at 200 g, and resuspended in 0.04% BSA in PBS for counting. After counting, 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. Libraries were pooled and sequenced using the NovaSeq (Ilumina; S1 flow cell) with 150bp paired end reads with 28 cycles for read1, 91 cycles for read2 8 cycles for i7 and 0 cycles for i5, and with a read depth of at least 25-30 000 pair reads per cell. Illumina NovaSeq 6000 SRX14130514 GSM5885677_r1 SRP359249 PRJNA805223 SRS11957076 GSM5885677 GSM5885677 RNA-Seq TRANSCRIPTOMIC cDNA Epicardioids were dissociated with papain as described in methods of Meier et al. (2021), filtered through 40 μm filter, washed with 5 mL 1% BSA (Gibco; 15260037) in PBS-/-, centrifuged for 3 min at 200 g, and resuspended in 0.04% BSA in PBS for counting. After counting, 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. Libraries were pooled and sequenced using the NovaSeq (Ilumina; S1 flow cell) with 150bp paired end reads with 28 cycles for read1, 91 cycles for read2 8 cycles for i7 and 0 cycles for i5, and with a read depth of at least 25-30 000 pair reads per cell. Illumina NovaSeq 6000 SRX14130515 GSM5885678_r1 SRP359249 PRJNA805223 SRS11957078 GSM5885678 GSM5885678 RNA-Seq TRANSCRIPTOMIC cDNA Epicardioids were dissociated with papain as described in methods of Meier et al. (2021), filtered through 40 μm filter, washed with 5 mL 1% BSA (Gibco; 15260037) in PBS-/-, centrifuged for 3 min at 200 g, and resuspended in 0.04% BSA in PBS for counting. After counting, 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. Libraries were pooled and sequenced using the NovaSeq (Ilumina; S1 flow cell) with 150bp paired end reads with 28 cycles for read1, 91 cycles for read2 8 cycles for i7 and 0 cycles for i5, and with a read depth of at least 25-30 000 pair reads per cell. Illumina NovaSeq 6000 SRX14130516 GSM5885679_r1 SRP359249 PRJNA805223 SRS11957079 GSM5885679 GSM5885679 RNA-Seq TRANSCRIPTOMIC cDNA Epicardioids were dissociated with papain as described in methods of Meier et al. (2021), filtered through 40 μm filter, washed with 5 mL 1% BSA (Gibco; 15260037) in PBS-/-, centrifuged for 3 min at 200 g, and resuspended in 0.04% BSA in PBS for counting. After counting, 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. Libraries were pooled and sequenced using the NovaSeq (Ilumina; S1 flow cell) with 150bp paired end reads with 28 cycles for read1, 91 cycles for read2 8 cycles for i7 and 0 cycles for i5, and with a read depth of at least 25-30 000 pair reads per cell. Illumina NovaSeq 6000 SRX14130517 GSM5885680_r1 SRP359249 PRJNA805223 SRS11957080 GSM5885680 GSM5885680 RNA-Seq TRANSCRIPTOMIC cDNA Epicardioids were dissociated with papain as described in methods of Meier et al. (2021), filtered through 40 μm filter, washed with 5 mL 1% BSA (Gibco; 15260037) in PBS-/-, centrifuged for 3 min at 200 g, and resuspended in 0.04% BSA in PBS for counting. After counting, 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. Libraries were pooled and sequenced using the NovaSeq (Ilumina; S1 flow cell) with 150bp paired end reads with 28 cycles for read1, 91 cycles for read2 8 cycles for i7 and 0 cycles for i5, and with a read depth of at least 25-30 000 pair reads per cell. Illumina NovaSeq 6000 SRX14130518 GSM5885681_r1 SRP359249 PRJNA805223 SRS11957081 GSM5885681 GSM5885681 RNA-Seq TRANSCRIPTOMIC cDNA Epicardioids were dissociated with papain as described in methods of Meier et al. (2021), filtered through 40 μm filter, washed with 5 mL 1% BSA (Gibco; 15260037) in PBS-/-, centrifuged for 3 min at 200 g, and resuspended in 0.04% BSA in PBS for counting. After counting, 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. Libraries were pooled and sequenced using the NovaSeq (Ilumina; S1 flow cell) with 150bp paired end reads with 28 cycles for read1, 91 cycles for read2 8 cycles for i7 and 0 cycles for i5, and with a read depth of at least 25-30 000 pair reads per cell. Illumina NovaSeq 6000 SRX14130519 GSM5885682_r1 SRP359249 PRJNA805223 SRS11957082 GSM5885682 GSM5885682 RNA-Seq TRANSCRIPTOMIC cDNA Epicardioids were dissociated with papain as described in methods of Meier et al. (2021), filtered through 40 μm filter, washed with 5 mL 1% BSA (Gibco; 15260037) in PBS-/-, centrifuged for 3 min at 200 g, and resuspended in 0.04% BSA in PBS for counting. After counting, 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. Libraries were pooled and sequenced using the NovaSeq (Ilumina; S1 flow cell) with 150bp paired end reads with 28 cycles for read1, 91 cycles for read2 8 cycles for i7 and 0 cycles for i5, and with a read depth of at least 25-30 000 pair reads per cell. Illumina NovaSeq 6000 SRX14130520 GSM5885683_r1 SRP359249 PRJNA805223 SRS11957083 GSM5885683 GSM5885683 RNA-Seq TRANSCRIPTOMIC cDNA Epicardioids were dissociated with papain as described in methods of Meier et al. (2021), filtered through 40 μm filter, washed with 5 mL 1% BSA (Gibco; 15260037) in PBS-/-, centrifuged for 3 min at 200 g, and resuspended in 0.04% BSA in PBS for counting. After counting, 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. 8 000 cells for each sample (targeted cell recovery) were processed using Chromium Single Cell 3' GEM, Library & Gel Bead Kit v3 (10x Genomics; PN-1000092), the Chromium Chip B Single Cell Kit (10x Genomics; PN- 1000073), and the Chromium i7 Multiplex Kit v2 (10x Genomics; PN-120262) for samples d2-d15 and Chromium Next GEM Single Cell 3' Library & Gel Bead Kit v3.1 (1000128, 10x Genomics) Chromium Single Cell G Chip Kit (1000127, 10x Genomics) and Single Index Kit T Set A (PN-1000213, 10x Genomics) for sample d30 to generate Gel Bead-In-EMulsions (GEMs) and single cell sequencing libraries. Libraries were pooled and sequenced using the NovaSeq (Ilumina; S1 flow cell) with 150bp paired end reads with 28 cycles for read1, 91 cycles for read2 8 cycles for i7 and 0 cycles for i5, and with a read depth of at least 25-30 000 pair reads per cell. Illumina NovaSeq 6000