Cardiac Rehabilitation by Pulmonary Artery Banding after Induced Dilated Cardiomyopathy: A Pilot Study on a Rodent Model

Background: Since 2015, the pulmonary artery banding (PAB), following the Giessen protocol, has treated end- stage heart failure in selected infants with preserved right ventricular function, acting as a bridge to transplant or recovery, as a result of ventricular-ventricular interaction. Objectives: To elucidate whether PAB is a feasible and reproducible procedure in a rodent model of pharmacologically induced dilated cardiomyopathy (DCM) and to evaluate PAB-induced ventricular rehabilitation. Methods: We used 49 Sprague-Dawley rats divided into four groups: a sham surgery control group, a healthy animal group undergoing PAB, a doxorubicin (DOX)- treated control group, and a DOX + PAB-treated group. All underwent echocardiographic, histological, and molecular analyses. Results: Preliminary results showed high mortality in rats with DOX-induced DCM, with contractile dysfunction confirmed by 2D echocardiography. Signs of damage were detected through transmission electron microscopy, but not via standard histological/molecular tests. PAB after DOX improved contractile function, enhancing ejection fraction (p = 0.01) and fractional shortening (p = 0.03). Conclusion: The DOX-induced DCM model, while reproducible, may not reflect DCM's true pathology. High mortality and individual variability limited the study. Further research is needed to fi nd alternative models with lower mortality and to explore the PAB-induced molecular signaling pathways and cardiac proliferation potential.