Multicellular signaling and partial recovery define reverse cardiac remodeling
Heart failure results from maladaptive multicellular remodeling triggered by sustained biomechanical stress. Although mechanical unloading can promote reverse remodeling, recovery is frequently incomplete and its mechanistic basis remains unclear. Using a reversible murine pressure-overload model combined with bulk and single-nucleus transcriptomics, we demonstrate that reverse remodeling represents an actively maintained yet constrained multicellular state. Unloading improved cardiac function and partially restored extracellular matrix and metabolic programs, whereas inflammatory and mitochondrial dysfunction signatures persisted. Cardiomyocytes and endothelial cells largely re-established homeostatic transcriptional states, while fibroblasts retained activated programs that dominated residual pathology. Multicellular factor analysis delineated a reversible metabolic stress program and a persistent inflammatory-mitochondrial program coordinated across cardiac cell types. Cell-cell communication analysis identified lymphatic endothelial cells as key instructive regulators of recovery. Notably, lymphatic-derived Reelin directly suppressed pathological fetal gene activation in murine and human cardiomyocytes, uncovering a previously unrecognized lymphoangiocrine mechanism that constrains myocardial recovery in chronic heart failure.