Total Liquid Ventilation Provides Ultra-Fast Cardioprotective Cooling Original Research Article

Objectives We tested whether total liquid ventilation (TLV) can be used to rapidly cool and protect the infarcting heart. Background Decreasing myocardial temperature during ischemia is a powerful cardioprotective strategy, but clinical application has been impaired by lack of practical methodology to quickly cool the heart. Methods We performed 30-min coronary artery occlusion/3-h reperfusion in rabbits. Upon occlusion, rabbits underwent either oxygen (Gas), normothermic liquid (Liquid Warm), or cold liquid (Liquid Cool) ventilation. Results Left atrial chamber temperature decreased to 32.4° ± 0.2°C within 5 min of onset of cold TLV. Blood gases were within acceptable limits during TLV. In the Liquid Warm group, perfluorocarbon inhalation did not alter infarct size compared with Gas (37.7 ± 1.3% and 42.5 ± 4.9% of risk zone, respectively). However, infarction was significantly reduced in the Liquid Cool group (4.0 ± 0.5%). Cooling only during the initial 30 min of reperfusion did not reduce infarction. Conclusions Total liquid ventilation can elicit rapid cardioprotective cooling during ischemia.