Intracoronary hypothermia for acute myocardial infarction in the isolated beating pig heart.
Hypothermia may attenuate reperfusion injury and thereby improve acute myocardial infarction therapy. Systemic cooling trials failed to reduce infarct size, perhaps because the target temperature was not reached fast enough. The use of selective intracoronary hypothermia combined with intracoronary temperature monitoring allows for titrating to target temperature and optimizing the cooling rate. We aimed to the test the feasibility of intracoronary cooling for controlled, selective myocardial hypothermia in an isolated beating pig heart. In five porcine hearts the left anterior descending artery (LAD) was occluded by an over-the-wire balloon (OTWB). After occlusion, saline at 22°C was infused through the OTWB lumen for 5 minutes into the infarct area at a rate of 30 ml/min. Thereafter the balloon was deflated but infusion continued with saline at 4°C for 5 minutes. Distal coronary temperature was continuously monitored by a pressure/temperature guidewire. Myocardial temperature at several locations in the infarct and control areas was recorded using needle thermistors. In the occlusion phase, coronary temperature decreased by 11.4°C (range 9.4-12.5°C). Myocardial temperature throughout the infarct area decreased by 5.1°C (range 1.8-8.1°C) within three minutes. During the reperfusion phase, coronary temperature decreased by 6.2°C (range 4.1-10.3°C) and myocardial temperature decreased by 4.5°C (range 1.5-7.4°C). Myocardial temperature outside the infarct area was not affected. In the isolated beating pig heart with acute occlusion of the LAD, we were able to rapidly "induce, maintain, and control" a stable intracoronary and myocardial target temperature of at least 4°C below body temperature without side effects and using standard PCI equipment, justifying further studies of this technique in humans.
Department of Cardiology, Catharina Hospital EindhovenEindhoven, The Netherlands; Department of Biomedical Engineering, Eindhoven University of TechnologyThe Netherlands.
Luuk C
LC
Otterspoor
Department of Cardiology, Catharina Hospital EindhovenEindhoven, The Netherlands; Department of Biomedical Engineering, Eindhoven University of TechnologyThe Netherlands.
Lokien X
LX
van Nunen
Department of Biomedical Engineering, Eindhoven University of Technology The Netherlands.
Tilaï T
TT
Rosalina
Department of Cardiology, Catharina Hospital EindhovenEindhoven, The Netherlands; Department of Biomedical Engineering, Eindhoven University of TechnologyThe Netherlands.
Marcel Van't
MV
Veer
Life Tec Group Eindhoven, The Netherlands.
Sjoerd Van
SV
Tuijl
Life Tec Group Eindhoven, The Netherlands.
Marco
M
Stijnen
Department of Biomedical Engineering, Eindhoven University of Technology The Netherlands.
Marcel Cm
MC
Rutten
Department of Biomedical Engineering, Eindhoven University of Technology The Netherlands.
Frans N
FN
van de Vosse
Department of Cardiology, Catharina Hospital EindhovenEindhoven, The Netherlands; Department of Biomedical Engineering, Eindhoven University of TechnologyThe Netherlands.
Nico Hj
NH
Pijls
Intracoronary hypothermia; acute myocardial infarction; reperfusion injury