Researchers at Mount Sinai demonstrated that delivering the gene Cyclin A2 (CCNA2) via a human‑compatible viral vector can induce cytokinesis in adult human cardiomyocytes and promote cardiac repair in preclinical models. Time‑lapse imaging showed treated cells entered division and produced functional daughter cells while preserving contractile proteins and calcium handling. The team tested cells from donors aged 21 to 55 and observed successful division in middle‑aged samples, suggesting potential translational relevance for heart failure therapy. Authors noted the need for further safety and efficacy studies to assess arrhythmia risk, vector biodistribution, and durability before clinical trials.