Facilitated Myocardial Ablation Using Heat-Sensitive Liposomes Containing Doxorubicin

The authors sought to evaluate a method for improving radiofrequency (RF) lesion durability using doxorubicin encased in heat-sensitive liposomes (HSL-dox). Using a porcine model, RF ablations were performed in the right atrium after systemic infusion of either HSL-dox or saline control given immediately before mapping and ablation. Lesion geometry was measured with voltage mapping immediately postablation and after 2 weeks of survival. After 2 weeks, lesions demonstrated less regression in scar area in HSL-dox–exposed animals compared with control animals. We demonstrate improved RF lesion durability in animals treated with HSL-dox, and the cardiotoxic effect was more pronounced after RF applications with higher power and longer duration.