Intracoronary-Cardiosphere-Derived Cell Secretome Therapy: Effects on Ventricular Tachycardia Inducibility and Cardiac Function in a Swine Model

<b>Background/Objectives:</b> Ventricular tachycardia (VT) resulting in sudden cardiac death is common following a myocardial infarction (MI). Our objective was to evaluate the effects of an intracoronary (IC) administration of cardiosphere-derived cell secretome (S-CDCs) on VT inducibility and cardiac function in a swine model of MI. <b>Methods:</b> Fourteen pigs underwent endovascular MI model creation. At 4 weeks, saline (CON; 5 mL; n = 7) or S-CDCs (S-CDCs; 9.16 mg protein in 5 mL saline; n = 7) was blindly administered via the IC route. VT inducibility and magnetic resonance imaging (MRI) studies were performed both pre- and 4 months post-IC therapy, calculating left ventricular ejection fraction (LVEF), infarct size as a percentage of left ventricle (% MI), and left ventricular indexed end-diastolic and end-systolic volumes (LVEDVi, LVESVi). <b>Results:</b> While VT was inducible in 100% of the animals before IC therapy, at 4 months, the inducibility rate was lower in the S-CDCs group compared to the CON group (57% versus 100%, <i>p</i> = 0.05). Likewise, in the S-CDCs group, % MI was significantly lower than in the CON group (12 ± 3% versus 16 ± 3%, <i>p</i> = 0.03). LVEF (S-CDCs: 35 ± 10% versus CON: 29 ± 10%, <i>p</i> = NS), LVEDVi and LVESVi (S-CDCs: 83 ± 18 mL/m² and 56 ± 20 mL/m² versus CON: 88 ± 29 mL/m² and 64 ± 20 mL/m², <i>p</i> = NS) did not change. <b>Conclusions:</b> IC therapy with S-CDCs appears to reduce the development of post-MI VT. Furthermore, it suggests a beneficial effect on infarct size, reducing % MI in this experimental swine model.